Field of the Disclosure
Examples of the present disclosure are related to systems and methods for a paralleled hybrid horticulture system. More particularly, embodiments disclose utilizing a constant power (CP) power supply that is configured to operate in a constant voltage or constant current mode, wherein the maximum current and maximum voltage conditions may be programed based on the characteristics of a LED bar.
Background
Conventional LEDs emit light through the conversion of electrons to photons. As the rate of electrons (current) increases, the number of emitted photons (radiometric flux) proportionally increases. Since LEDs are not 100% efficient (electron to photon conversion), heat proportionally increases as a function of current. At extreme currents, quantum wells associated with the LEDs can get saturated, and therefore higher current leads to less light output. IV curves for LEDs allow for a direct correlation between the voltage and the current through the LEDs. Based on the IV curves, LEDs are sensitive to overvoltage conditions. In an overvoltage condition, the voltage in a circuit is raised above its upper design limit.
Since voltage is a function of current, a voltage rise above the design limits in-turn pushes current through the LEDs above the design limits. Considerable damage can be caused to electrical devices by the voltage surge creating over voltage conditions than that for which the devices are rated for. For example, when overvoltage/current occurs, an LED may stop working due to breakage in the circuit (wirebond breaking, traces burn up) and overheating (material property changes as a function of heat).
Conventionally light fixtures include a plurality of LED strings that are coupled in parallel with a constant current (CC) power supply. Utilizing the CC power supply, current is evenly distributed to each of the LED strings based on the forward voltage of the LED strings. Because the forward voltages of the LED strings are consistent, the currents applied to each LED string are consistent.
However, if a number of LED strings coupled to the CC power supply drops below a given threshold, such as a single LED string, then all of the current from the CC power supply passes through the single LED string. This causes the single LED string to be overdriven, overheat, and prematurely fail.
Accordingly, needs exist for more effective and efficient systems and methods for paralleled hybrid horticulture systems, which utilize constant current and/or constant power supplies.